Before Ornish published his clinical studies of patients whose cardiovascular problems were improved by diet and other means, doctors believed that heart disease was irreversible.
Origins
It took Ornish several published studies before conventional medicine would accept his position that simple and inexpensive treatments, including diet, exercise, and stress reduction, could reverse heart disease.
Ornish believed that therapies for heart disease should confront the roots of the problem—high-fat diets, stress, and sedentary lifestyles—instead of more expensive and risky heart surgery.
Beginning in 1980, Ornish studied 48 people with severe heart disease. Half of them were assigned to a control group and were treated by conventional methods, while the other half participated for three weeks in Ornish’s program of an ultra-low fat diet, yoga, meditation, social support groups, and no cigarettes.
The diet that Ornish designed was similar to the regimen developed in the 1970s by Nathan Pritikin to combat heart disease, which is still used in several clinics. Both diets emphasize foods that are very low in fat and yet filling, including high-fiber grains and legumes (beans and peas).
Over the course of the study, Ornish’s group experienced improvement in symptoms and significant drops in cholesterol and blood pressure. Ornish published the results in the prestigious Journal of the American Medical Association, and his study was met with controversy.
To convince his critics, Ornish set up a long-term controlled study. After one year, patients treated with Ornish’s methods showed convincing results: 82% of them had significantly less blockage in their heart arteries and there was a drop of 91% in reported chest pain.
After that study was published in the British medical journal Lancet, Ornish became internationally famous, and the Ornish diet was adopted by many heart disease patients. Ornish now serves as president of the Preventive Medicine Research Institute in Sausalito, California, and as a professor at the University of California.
Benefits
The Ornish diet has also been shown to be an effective weight loss program, and is recommended as a preventive measure for heart disease, strokes, diabetes and other conditions related to high fat consumption. The Ornish diet is an easy and inexpensive form of treatment as well as a preventive measure.
Description
Heart disease develops when arteries that supply the heart with oxygen become narrowed due to the buildup of plaque on their walls. Plaque deposits are caused by cholesterol, a type of fat found in animal products and also made by the body from saturated fats in the diet.
The narrowing of arteries is called atherosclerosis, a condition that develops over many years. When the coronary (heart) arteries become too blocked to supply the heart with enough oxygen, a heart attack occurs.
The first principle of the Ornish diet is to eliminate cholesterol, so all foods containing cholesterol and saturated fats are removed from the diet. Saturated fats are found in meat, dairy products, oils, nuts, seed, and avocados, which are all forbidden by the Ornish diet.
Furthermore, the level of fat in the diet is reduced to only 10% of the total calories. This level is much lower than the diet recommended by the American Heart Association, which recommends up to 30% of calories from fat.
The typical American diet consists of up to 50% fat. The Ornish diet is vegetarian, since cholesterol-containing meats are eliminated. The diet allows the use of egg whites and nonfat dairy products; technically it can be classified as a lacto-ovo-vegetarian diet.
Another feature of the Ornish diet is the ratios assigned to fat, protein, and carbohydrates, respectively. The typical American diet is 45% fat, 25% protein and 30% carbohydrates, with nearly 500 mg of cholesterol per day. The Ornish diet is 10% fat, 20% protein, and 70% carbohydrates. The Ornish diet consists mainly of complex carbohydrates, commonly called starches.
Complex carbohydrates are present in fruits, vegetables, grains, and beans. Simple carbohydrates include sugar, honey, and alcohol, which tend to be “empty calories,” because they contain lots of calories but little fiber or nutrients.
The Ornish diet restricts but does not eliminate simple carbohydrates. The Ornish diet also emphasizes high-fiber foods, which includes most complex carbohydrates. High-fiber diets have been shown to reduce cholesterol and have other beneficial effects.
The Ornish diet is slightly lower in protein than the American average, and lower protein intake has been shown by research to have potential health benefits for Americans. For those worried about the lack of protein in a vegetarian diet, the Ornish program teaches ways to ensure an adequate supply of complete proteins in the diet.
Proteins are said to be complete when the body can fully utilize them. They can be obtained by combining grains with legumes (beans) or grains with nonfat dairy products.
For instance, complete proteins in the Ornish diet are obtained by combining rice and beans, tofu and rice, pasta and beans, baked beans and wheat bread, or oatmeal with nonfat yogurt over the course of a day. Egg whites are another source of protein on the Ornish diet.
Another principle of the Ornish diet is that people are allowed to eat as much food as they wish, as long as the 10%-of-calories-from-fat rule is maintained, and as long as only approved foods are eaten.
By allowing people to eat as much as they like, the Ornish diet reduces the risk of binge eating, to which many dieters resort when forced to restrict calories. Many diets have been shown to fail when calories are restricted.
To summarize, the Ornish diet excludes cholesterol and saturated fat, including all animal products (except egg whites and nonfat dairy products), nuts, seeds, avocados, chocolate, olives, and coconuts.
Oils are eliminated except a small amount of canola oil for cooking, and oil that supplies omega-3 essential fatty acids. The Ornish diet also prohibits caffeine, but allows a moderate intake of alchohol, sugar, and salt.
It should be noted that Ornish himself states that his diet alone is not sufficient for reversing heart disease, but is only one part of an overall program that includes exercise, yoga, meditation, stress reduction, and lifestyle changes.
In fact, Ornish calls some of his work “opening the heart” therapies, because patients are encouraged to confront emotional aspects of their healing as well as physical concerns like diet and high cholesterol.
Preparations
Ornish states that one emphasis of his program is increasing the awareness of eating habits and the ingredients of food products. Those beginning the Ornish diet can prepare by becoming thoroughly familiar with Ornish’s list of recommended and prohibited foods, and by learning to read food labels and count calories.
Another preparation dieters can make is determining their ideal weight for their particular height and body type. Daily calorie and fat allowances can then be derived from this ideal weight. Ornish has authored or co-authored several books that provide hundreds of recipes consistent with the diet.
Precautions
The Ornish diet is not a substitute for medical care of cardiovascular disease. Furthermore, the Ornish diet is designed to be used in conjunction with a holistic health program that includes exercise, yoga, meditation, lifestyle changes, and stress reduction. As with any diet program, research continues on its effectiveness.
Critics of the program maintain that Dr. Ornish has not produced sufficient clinical research to support his claims and that a diet high in carbohydrates will drive up insulin levels, increasing the risk of diseases such as diabetes.
A 2003 study comparing low-fat diets to low-carbohydrate diets reported that obese patients lost more weight on the low-carbohydrate diet compared to a fat and calorie-restricted diet. They also appeared to have lower triglyceride levels and improved insulin sensitivity.
Those considering the Ornish diet should check with their physician and remain alert to recommendations from organizations such as the American Heart Association for diet and exercise guidelines.
Posted in: food
Related Post:
Widget by [ Iptek-4u ]
